The Flex SDK includes three Remote Procedure Call (RPC) components that allow you to integrate your Flex applications with common application server products. Of these, the HTTPService component has the most flexibility in terms of the format of messages that are exchanged between the client and server at runtime. Unlike the other RPC components (WebService and RemoteObject), you can use the HTTPService component with any application server because it exchanges data in the form of simple HTTP parameters and XML of any flavor.

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